Address some comments and clean up

Change-Id: I538cf204f1c89d5fc81f8fc5e5800fcf1cf87359
diff --git a/runtime/runtime.cc b/runtime/runtime.cc
index a27acb2..b08e521 100644
--- a/runtime/runtime.cc
+++ b/runtime/runtime.cc
@@ -1516,7 +1516,7 @@
 
 void Runtime::AllowNewSystemWeaks() {
   monitor_list_->AllowNewMonitors();
-  intern_table_->ChangeWeakRootState(gc::kWeakRootStateNormal);  // TODO: Do this in the sweeping?
+  intern_table_->ChangeWeakRootState(gc::kWeakRootStateNormal);  // TODO: Do this in the sweeping.
   java_vm_->AllowNewWeakGlobals();
   heap_->AllowNewAllocationRecords();
   lambda_box_table_->AllowNewWeakBoxedLambdas();